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Title: Imaging and Segmenting Grains and Subgrains Using Backscattered Electron Techniques

Journal Article · · Microscopy and Microanalysis

We present two new methods of processing data from backscattered electron signals in a scanning electron microscope to image grains and subgrains. The first combines data from multiple backscattered electron images acquired at different specimen geometries to (1) better reveal grain boundaries in recrystallized microstructures and (2) distinguish between recrystallized and unrecrystallized regions in partially recrystallized microstructures. The second utilizes spherical harmonic transform indexing of electron backscatter diffraction patterns to produce high angular resolution orientation data that enable the characterization of subgrains. Subgrains are produced during high-temperature plastic deformation and have boundary misorientation angles ranging from a few degrees down to a few hundredths of a degree. Here, we also present an algorithm to automatically segment grains from combined backscattered electron image data or grains and subgrains from high angular resolution electron backscatter diffraction data. Together, these new techniques enable rapid measurements of individual grains and subgrains from large populations.

Research Organization:
Florida State University, Tallahassee, FL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Accelerator R&D and Production (ARDAP); National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
Grant/Contract Number:
SC0009960; 89233218CNA000001; NA0003525
OSTI ID:
2477931
Journal Information:
Microscopy and Microanalysis, Journal Name: Microscopy and Microanalysis Journal Issue: 5 Vol. 30; ISSN 1431-9276
Publisher:
Microscopy Society of America (MSA)Copyright Statement
Country of Publication:
United States
Language:
English

References (26)

The dislocation microstructure of aluminum journal May 1987
Flow stress, subgrain size, and subgrain stability at elevated temperature journal June 1977
Dynamic Grain Growth Driven by Subgrain Boundaries in an Interstitial-Free Steel During Deformation at 850 °C journal December 2023
Graph-cut methods for grain boundary segmentation journal July 2011
Mechanical behavior of crystalline solids at elevated temperature journal January 1968
Automatic grain boundary detection and grain size analysis using polarization micrographs or orientation images journal July 2000
SEraMic: A semi-automatic method for the segmentation of grain boundaries journal August 2021
Identification of sub-grains and low angle boundaries beyond the angular resolution of EBSD maps journal December 2014
c-Axis orientation determination of α-titanium using Computational Polarized Light Microscopy journal September 2020
Microstructure segmentation using multi-angle polarized light microscopy journal October 2022
Grain detection from 2d and 3d EBSD data—Specification of the MTEX algorithm journal December 2011
Dark-field imaging based on post-processed electron backscatter diffraction patterns of bulk crystalline materials in a scanning electron microscope journal January 2015
Electron imaging with an EBSD detector journal January 2015
A spherical harmonic transform approach to the indexing of electron back-scattered diffraction patterns journal December 2019
High-precision orientation mapping from spherical harmonic transform indexing of electron backscatter diffraction patterns journal March 2021
Comparison of Channeling Contrast between Ion and Electron Images journal March 2013
EMsoft: open source software for electron diffraction/image simulations journal July 2017
Backscattered Electron Imaging with an EBSD Detector journal January 2015
Practical, Unified, Motion and Missing Data Treatment in Degraded Video journal January 2004
Efficient Graph-Based Image Segmentation journal September 2004
Fiji: an open-source platform for biological-image analysis journal June 2012
Electron channeling patterns in the scanning electron microscope journal August 1982
Statistical Comparison of Substructures in Pure Aluminum Before and After Creep Deformation, Based on EBSD Image Data journal November 2023
A Threshold Selection Method from Gray-Level Histograms journal January 1979
On the High-Temperature Creep Behaviour and Substructures in Alpha-Iron Single Crystals journal January 1972
Texture Analysis with MTEX – Free and Open Source Software Toolbox journal February 2010